Mobilinkd TNC2: Bluetooth APRS on the cheap!

I recall reading about the original TNC1 a few years back and only recently realized WX9O has been a busy guy working on TNC2.

And, at a recent OMARC meeting when I started talking with Joe KD2AKU about doing packet with the MPET in an almost opensource way similar to what the GoTenna is but as a ham only version since the GoTenna is encrypted ( a big no no for ham radio) and only on MURS - this gave me an idea for the MPET as noted in the other thread.

So this is part gear review, part other stuff.

This all was part inspiration for my AX.25 MPET project found "somewhere" else on this fancy OMARC Forum. Felt it good to post a gear review.

What the heck is a Mobilinkd TNC2?

It is the cheapest and "bestest" way to get into APRS. All you need is a smartphone and ANY 2m radio (handheld or otherwise) in addition to the TNC2. In the little black box is basically an Arduino and a Bluetooth module along with a lithium battery and charger circuit. Much more detail can be found on the Mobilinkd website.

The TNC2 is what is known as a KISS TNC, meaning its just the modem end and does not have any memory or other "smart" control capability, like a KPC-3+ or other TNC's out there. For the TNC2 to work, it needs some brains and that is where the smart phone comes in. Here I am in San Francisco using the TNC2 with a Yaesu FT-60.

Why is it the "bestest" way K2GOG?

It's because anything with Bluetooth connectivity makes things better, that is why.  Plus its cheap. Sure, you could get a cable like this one and plug your radio into your smartphone, like what some people do with a Baofeng, but I HATE Baofeng radios and possibly "blowing out" my headphone jack on my smartphone is NOT FUN  . Plus, the cable route uses VOX and it wont be as reliable since the TNC2 essentially creates a wireless serial connection (SPP profile for those familiar with the BT stack), so its almost like a hard wired connection and not needing to rely on voice activation to key the transmitter.

So since Bluetooth makes this the "bestest", please explain more on what this does

Simply, you plug in the TNC2 to your radio, pair your smartphone to the TNC2, toss it into a backpack (or clip to your belt for you super awesome ham radio SPEC OPs out there) and that's it. You use your smartphone to view your location on a map and send/receive messages to other stations on APRS, local or otherwise.

I need to understand more about how this works

Step 1: Download two applications to your smartphone. APRSdroid and Mobilinkd TNC Config

Step 2: There is lots of documentation out there to give you a more detailed step by step, but all you do is FIRST configure the TNC2 audio settings with the Mobilinkd TNC Config application (see below input and output screens) and then disconnect and close that application.

Step 3: Open up the APRsdroid application, after you have it properly registered, etc and set the TNC up and create your APRS path (WIDE1-1 is best for most places) and that its.

Explain: Again, why is this the "bestest" ?

Manipulating the audio levels for most sound card based TNC's can be tricky. This is straight forward. It is also very light weight which is handy if you are traveling or supporting a special event and you dont want to go buy an "all in one" APRS handheld radio like the Yaesu VX-8r ($350), Yaesu FT-1XDR ($330), Kenwood THD72 ($399) or the super fancy and NEW Kenwood THD74 ($600+), which still dont show you anything too visual and they do not have Bluetooth to connect to a smartphone.

The only thing you need tk do with your radio aside from plug the TNC2 into it and march the audio level is to tune your radio to 144.390, which is where APRS operations are located in the US market.

Alternate radio options with APRS built in

You can buy an inexpensive 2m or multiband HT and with the TNC2, add APRS capability to it. You could even purchase two TNC2's and 2 more common HT's like a Yaesu FT-60 or an Icom T-70 for the cost of just one Kenwood THD74!!

Note: You could do also use the TNC2 with a cheapo Baofeng, I just don't like them but they are ok radios.

You still don't have me convinced. No one uses APRS or packet around here.

OMARC operates a APRS digipeater from the same location as our 805 repeater, and it gets amazing coverage to fill in gaps around other digipeaters in the area. There are also many users on daily on APRS. During special events, many more people come out of the so-called woodwork. Here is a screen grab with my TNC2 paired to my HT on the kitchen table here in FN31AW (where?) earlier this weekend that shows the coverage of the OMARC digipeater.

Imagine, if we started our own data network for packet based mail, using winlink? WE CAN DO THAT! IF we take some functions from the TNC2 and integrate it into the MPET, per this thread.